Schisandrin B protects human keratinocyte-derived HaCaT cells from tert-butyl hydroperoxide-induced oxidative damage through activating the Nrf2 signaling pathway

Schisandrin B Alleviates LPS Induced Mitochondrial Damage in C28I2 Cells

Osteoarthritis is a common joint disease characterized by damage to the joint cartilage that occurs throughout the entire joint tissue. This damage primarily manifests as pain in the affected area. In clinical practice, medication is commonly used to relieve pain, but the treatment's effectiveness is poor and recurrent attacks are likely. Schisandrin B is the most abundant biphenylcyclohexene lignan found in the traditional Chinese medicine Schisandra chinensis, and it possesses various pharmacological effects. This study aims to investigate the protective effect of Schisandrin B on mitochondrial damage in osteoarthritis (C28I2 cells) under an inflammatory environment induced by LPS. Cell proliferation and activity, scratch tests, and LDH release tests are utilized to assess cell growth and migration ability. The immunofluorescence assay was used to detect the expression levels of proliferation and apoptosis proteins. The Western Blot assay was used to detect the expression levels of mitochondrial fusion and division proteins. The JC-1 assay was used to detect changes in mitochondrial membrane potential. The mitochondrial fluorescence probe assay was used to detect mitochondrial activity. Through research, it was found that Schisandrin B promotes the proliferation, growth, and migration of C28I2 cells, reduces apoptosis of C28I2 cells, balances mitochondrial fusion and division, stabilizes mitochondrial membrane potential, and promotes mitochondrial activity in an LPS induced inflammatory environment.

Lignans as Pharmacological Agents in Disorders Related to Oxidative Stress and Inflammation: Chemical Synthesis Approaches and Biological Activities

Plant lignans exhibit a wide range of biological activities, which makes them the research objects of potential use as therapeutic agents. They provide diverse naturally-occurring pharmacophores and are available for production by chemical synthesis. A large amount of accumulated data indicates that lignans of different structural groups are apt to demonstrate both anti-inflammatory and antioxidant effects, in many cases, simultaneously. In this review, we summarize the comprehensive knowledge about lignan use as a bioactive agent in disorders associated with oxidative stress and inflammation, pharmacological effects in vitro and in vivo, molecular mechanisms underlying these effects, and chemical synthesis approaches. This article provides an up-to-date overview of the current data in this area, available in PubMed, Scopus, and Web of Science databases, screened from 2000 to 2022.

Antioxidant Effects of Schisandra chinensis Fruits and Their Active Constituents

Schisandra chinensis Turcz. (Baill.) fruits, their extracts, and bioactive compounds are used in alternative medicine as adaptogens and ergogens protecting against numerous neurological, cardiovascular, gastrointestinal, liver, and skin disorders. S. chinensis fruit extracts and their active compounds are potent antioxidants and mitoprotectors exerting anti-inflammatory, antiviral, anticancer, and anti-aging effects. S. chinensis polyphenolic compounds-flavonoids, phenolic acids and the major constituents dibenzocyclooctadiene lignans are responsible for the S. chinensis antioxidant activities. This review will focus on the direct and indirect antioxidant effects of S. chinensis fruit extract and its bioactive compounds in the cells during normal and pathological conditions.

Carnosine Stimulates Macrophage-Mediated Clearance of Senescent Skin Cells Through Activation of the AKT2 Signaling Pathway by CD36 and RAGE

Background: Macrophages can selectively recognize and eliminate senescent cells, but this function is impaired with age, resulting in excessive accumulation of senescent cells in the skin, which ultimately causes skin aging. Therefore, enhancing the immune surveillance ability of macrophages to clear senescent keratinocytes and fibroblasts from aging skin may be an effective skin rejuvenation strategy.

Methods: In this study, a macrophage and senescent skin cell co-culture model was established whereby THP-1-derived macrophages and tert-butyl hydroxide-induced senescent skin cells (HaCaT and HFF-1) were grown in the same culture. Senescent skin cells were detected by the SPiDER-βgal assay, and the expression of secretory phenotype factors related to senescence was assayed by qPCR. The effect of carnosine on the number of SA-β-gal positive skin cells in the macrophage-senescent skin cell co-culture was evaluated and compared with that in the senescent skin cell monoculture.

Results: Carnosine promoted macrophage-mediated elimination of senescent skin cells in the co-culture. Through the AKT2 signaling pathway, carnosine upregulated the expression of CD36 and receptors for advanced glycation end products and elevated the phagocytic capacity of the macrophages, thereby promoting the ability of the macrophages to eliminate the senescent skin cells.

Conclusions: Carnosine could boost the immune surveillance ability of macrophages to clear senescent keratinocytes and fibroblasts in the macrophage-senescent skin cell co-culture by activating the AKT2 signaling pathway, suggesting the possibility of using carnosine as an agent to reverse skin aging.

Protective Effects of Oenothera biennis against Hydrogen Peroxide-Induced Oxidative Stress and Cell Death in Skin Keratinocytes

BACKGROUND

Oenothera biennis (evening primrose) produces bioactive substances with a diverse range of pharmacological functions. However, it is currently unknown whether extract prepared from the aerial parts of O. biennis (APOB) can protect the skin against oxidative stress.

OBJECTIVE

The aim of this study is to investigate the protective effects of APOB against oxidative stress-induced damage in human skin keratinocytes (HaCaT) and elucidate the underlying mechanisms.

METHODS

We pretreated HaCaT cells with various concentrations of APOB or the antioxidant N-acetyl-L-cysteine before applying H₂O₂. We then compared the cell viability, intracellular reactive oxygen species (ROS) production, and DNA and mitochondrial damage between pretreated and untreated control cells using a range of assays, flow cytometry, and Western blot analysis and also examined the reducing power and DPPH free radical scavenging activity of APOB.

RESULTS

APOB pretreatment significantly increased cell viability, effectively attenuated H₂O₂-induced comet tail formation, and inhibited H₂O₂-induced phosphorylation of the histone γH2AX, as well as the number of apoptotic bodies and Annexin V-positive cells. APOB was found to have high reducing power and DPPH radical scavenging activity and also exhibited scavenging activity against intracellular ROS accumulation and restored the loss of mitochondrial membrane potential caused by H₂O₂. APOB pretreatment almost totally reversed the enhanced cleavage of caspase-3, the degradation of poly (ADP-ribose)-polymerase (PARP), DNA fragmentation that usually occurs in the presence of H₂O₂, and increased the levels of heme oxygenase-1 (HO-1), a potent antioxidant enzyme that is associated with the induction of nuclear factor-erythroid 2-related factor 2 (Nrf2).

CONCLUSIONS

APOB can protect HaCaT cells from H₂O₂-induced DNA damage and cell death by blocking cellular damage related to oxidative stress via a mechanism that affects ROS elimination and by activating the Nrf2/HO-1 signaling pathway.

Schisandrin B Inhibits Osteoclastogenesis and Protects Against Ovariectomy-Induced Bone Loss

Osteoporosis is a systemic skeletal disease which is highly prevalent worldwide and considered to be associated with excessive bone resorption mediated by osteoclast. Osteoclast differentiation is featured by the activation of inflammation-related pathways and the generation of reactive oxygen species. Schisandrin B is a bioactive compound with strong antiinflammation and antioxidative properties, we thus speculated that Schisandrin B might serve as a potential candidate for osteoporosis. In the present study, we found that the formation and` function of osteoclasts were dramatically suppressed by Schisandrin B. And consistent with the in vitro results, treatment with Schisandrin B attenuated ovariectomy-induced bone loss in mice. Moreover, Schisandrin B notably inhibited the activation of mitogen activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) pathways and scavenged ROS by activating nuclear factor E2 p45-related factor 2 (Nrf2) signaling. In conclusion, our study indicates that Schisandrin B is an effective approach to treat osteoporosis and other osteoclast-related diseases.

Potential of Schisandra chinensis (Turcz.) Baill. in Human Health and Nutrition: A Review of Current Knowledge and Therapeutic Perspectives

Schisandra chinensis (Turcz.) Baill. (SCE) is a plant with high potential for beneficial health effects, confirmed by molecular studies. Its constituents exert anti-cancer effects through the induction of cell cycle arrest and apoptosis, as well as inhibition of invasion and metastasis in cancer cell lines and experimental animals. SCE displays antimicrobial effects against several pathogenic strains. It has anti-diabetic potential, supported by hypoglycemic activity. A diet rich in SCE improves pancreatic functions, stimulates insulin secretion, and reduces complications in diabetic animals. SCE prevents lipid accumulation and differentiation of preadipocytes, indicating its anti-obesity potential. SCE exerts a protective effect against skin photoaging, osteoarthritis, sarcopenia, senescence, and mitochondrial dysfunction, and improves physical endurance and cognitive/behavioural functions, which can be linked with its general anti-aging potency. In food technology, SCE is applied as a preservative, and as an additive to increase the flavour, taste, and nutritional value of food. In summary, SCE displays a variety of beneficial health effects, with no side effects. Further research is needed to determine the molecular mechanisms of SCE action. First, the constituents responsible for its beneficial effects should be isolated and identified, and recommended as preventative nutritional additives, or considered as therapeutics.